Overriding the Display Name in the TO header of SIP INVITE

Anyone know of a good way to override the Display Name in the TO headers of a SIP INVITE?

Particularly, we’d like to do this when sending to a Ring Group. right now it comes without a display name at all, which causes the handset to display something different than we would prefer.

so:
Via: SIP/2.0/UDP 10.20.8.5:5060;branch=z9hG4bK49f6a5cc;rport=5060;received=10.20.8.5
From: “User Name” sip:[email protected];tag=as1c9af6e4
To: sip:[email protected]:5060;transport=udp;tag=1498231753
Call-ID: [email protected]:5060
CSeq: 102 INVITE
Accept-Language: en

would like to have the TO field changed as follows:
To: “My Ring Group Name” sip:[email protected]:5060;transport=udp;tag=1498231753

Possible?? Was thinking I’d have to pass it through extensions_custom.conf, but then realized that a ring group isn’t really an extension…